CYA Level

[djg9100]

I came across the CYA test comments using 1/2 pool water and 1/2 water with no CYA. I have been interpreting the results using my test kit [Taylor K-2006C] to be 125 or so. Using the 1/2+1/2 method it read 90, so that means CYA @ 180. All else is checking out ok. Looks like I need to drain and refill? Any additional suggestions or comments.

[Watermom]

It's kinda risky draining a pool completely for fear of it popping out of the ground if you have a high water table. Usually better to only do a partial drain and refill.

Another option is to just run a HiC2 pool --- high chlorine/high CYA. You can read more about the CYA and chlorine relationship here:>
http://pool9.net/cl-cya/

If you do decide to run a HiC2 pool, no more trichlor or dichlor as both of them will continue to add more CYA.

Hope this helps.

[djg9100]

Ok thanks. I will raise the chlorine level and see how we like it. Draining is not a big issue, low water table. Will raise it up to 8.

[djg9100]

Watermom

So no more tabs [trichlor], use bleach to keep FC up and maintain other chemistry. No health concerns with HiC2 pool?

[Watermom]

No, its fine and won't hurt a thing. Lots of people run HiC2 pools on purpose. An advantage of doing so is that it typically allows you to test and add chlorine (bleach) less often. The only drawback is that if your pool gets algae, it takes very high shock levels to clear it but as long as you are diligent about keeping your chlorine between the minimum and maximum of the range in the chart I listed above, you shouldn't have algae.

[djg9100]

I have read posts about High CYA causing some cloudiness, etc. Pool looks great during day and pretty good at nite. Notice a lot of particulates at night when light is on and especially near the light. High C2 pool with CYa levels at 150-180. Is is advisable to use a water clarifier, specifically Leslies "ultra bright" to remove some of whatever this is??CYA 150 ish, FC 9, CC 1..

Thanks for commentary

[Watermom]

If your numbers are right, then it appears that you are fighting something in the water. Anytime the CC is over 0.5ppm, you should shock the pool. Use the levels in the chart I linked above and shock the pool and maintain the high chlorine until you can meet three criteria:
1) You lose no more than 1ppm of FC overnight from sundown until within one hour of sunrise the next morning
2) You have no more than 0.5ppm of CC
3) Your water is clear.

Then, hold the chlorine high for one additional day and then let it drift down and keep it within the minimum/maximum range based on your CYA level.

[djg9100]

ok to use the hypo-chlorite granules 73% or will this cause other issues?

[BigDave]

Calcium hyochlorite will build calcium hardness in the pool. I don't see a CH value in this thread; temperature, TA and pH are also relevant. Would you please provide these readings?